Didda (c. 924-1003) was the ruling Queen of Kashmir for nearly 50 years (958-1003), first as regent then in her own right — founder of the Lohara dynasty. Called "the Catherine of Kashmir" by historians, she was politically ruthless yet a great patron of architecture and Buddhism.
Didda does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Didda reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.